Western American English (also known as Western U.S. English or in the U.S., simply, Western) is a variety of American English that largely unites the entire western half of the United States as a single dialect region, including the states of California, Nevada, Arizona, Utah, New Mexico, Colorado, and Wyoming. It also generally encompasses Washington, Oregon, Idaho, and Montana, some of whose speakers are classified additionally under Pacific Northwest English. The West was the last area in the United States to be reached during the gradual westward expansion of English-speaking settlement and its history shows considerable mixing of the linguistic patterns of other regions. As the settlement populations are relatively young when compared with other regions, the American West is a dialect region in formation.
The Western dialect of American English is somewhat variable and not necessarily distinct from "General American." Western American English is characterized primarily by two phonological features: the cot-caught merger (as distinct from most Northern and Southern U.S. English) and the fronting of but not (as distinct from most Southern and Mid-Atlantic American English, in which both of those vowels are fronted, as well as from most Northern U.S. English, in which both of these remain backed).
Like most Canadian dialects and younger General American, /?/ allophones remain back and may be either rounded or unrounded due to a merger between and (commonly represented in conservative General American, respectively, so that words like cot and caught, or pod and pawed, are perfect homophones (except in San Francisco). In the West, there is less Canadian raising of the diphthong than in Canada, and yet fairly common Canadian raising of the diphthong. A significant minority of Western speakers have the pin-pen merger or a closeness to the merger, especially around Bakersfield, California, though it is a sound typically associated with Southern U.S. dialect, which influenced the area. The West is entirely rhotic and the Mary-marry-merry merger is complete (as in most of North America), so that words like Mary, marry, and merry are all pronounced identically because of the merger of all three of those vowels' sounds when before r (towards [?]).
Several sub-types of the Western dialect exist or appear to be currently in formation. A noticeable California Vowel Shift has been observed in the English of some California speakers scattered throughout the state, though especially younger and coastal speakers. This shift involves two elements, including that the vowel in words like toe, rose, and go (though remaining back vowels elsewhere in the Western dialect), and the vowel in words like spoon, move, and rude are both pronounced farther forward in the mouth than most other English dialects; at the same time, a lowering chain movement of the front vowels is occurring (identical to the Canadian Vowel Shift), so that, to listeners of other English dialects, sit may approach the sound of set, set may approach sat, and sat may approach sot. This front-vowel lowering is also reported around Portland, Oregon, the hub of a unique Northwestern variety of American English that demonstrates other similarities with Canadian English. A trend evident particularly in some speakers from the Salt Lake City, Utah and Flagstaff, Arizona areas, as well as in some Californian and New Mexican English, is the completion or transition towards a full-fool merger.
Studies demonstrate that gender, age, and ability to speak Hawaiian Creole (a language locally called "Pidgin" and spoken by about two-fifths of Hawaiians) correlate with the recent emergence of different Hawaiian English accents. In a 2013 study of twenty O?ahu-raised native English speakers, those who do not speak Pidgin or are male were shown to lower and ; younger speakers of the first group also lowered , and younger participants in general backed . Though this movement of these vowels is superficially similar to the California Vowel Shift, it is not believed to be due to a chain shift, though Hawaiians do have a cot-caught merger, at least among younger speakers. Unlike most Americans, Hawaiians may not demonstrate any form of /æ/ tensing (even before nasal consonants, as with most Western Americans).
Currently, there is not enough data on the English of Alaska to either include it within Western American English or assign it its own "separate status". Of two documented speakers in Anchorage, their cot-caught merger is completed or transitional, is not fronted, is centralized, the placement of is inconsistent, and ag approaches the sound of egg. Not far from Anchorage, in Alaska's Matanuska-Susitna Valley, is an entirely separate accent: a Minnesota-like one in a dialect enclave of North-Central American English, due to immigration of Minnesotans to the valley in the 1930s.